/*
 * Copyright 2025 coze-dev Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import { compareNodePosition } from './compare-node-position';

export const findNotContainsPreviousSibling = (
  node: Node | null,
): Node | null => {
  if (!node || node === document) {
    return null;
  }

  let sibling: Node | null = node.previousSibling ?? node.parentNode;

  while (sibling) {
    if (sibling === document) {
      return null;
    }

    // Get the relationship between two nodes
    const relationship = compareNodePosition(sibling, node);

    // If there is no containing relationship between the two nodes, the current sibling is returned
    if (!['containedBy', 'contains'].includes(relationship)) {
      return sibling;
    }

    if (!sibling.previousSibling) {
      sibling = sibling.parentNode;
    } else {
      sibling = sibling.previousSibling;
    }
  }

  return null;
};
